select clienti where data < @Data1 And data > @Data2
Dim Data1 as Date=Date.Parse(Textbox1.text).AddMonths(1)
Dim Data2 as Date=Date.Parse(Textbox1.text)
TuoCommand.Parameters.Add(New Parameter With {.DbType=DbType.DateTime, .Value=Data1,.ParameterName="@Data1"})
TuoCommand.Parameters.Add(New Parameter With {.DbType=DbType.DateTime, .Value=Data2,.ParameterName="@Data2"})